The invention described herein was made in the course of or under a contract with the U.S. Department of Health, Education and Welfare.
The nearest known prior art is an article entitled "Studies on Mesoionic Compounds. III..sup.1) Synthesis of .psi.-3-Aryl-5-imino-3,5-dihydro-1-oxa-2,3,4-triazole Hydrochlorides and Their Derivatives" by Katsutada Masuda, Takaaki Kamiya, and Kenichi Kashiwa, published in the Chemical & Pharmaceutical Bulletin 19 (3) pp. 559 through 563 (1971). Among others, this article discloses compounds corresponding to the above structured formula, alleged to have utility as hypotensive agents, wherein R.sup.1 represents phenyl, o-tolyl and p-chlorophenyl and R.sup.2 is hydrogen. No compounds are disclosed wherein R.sup.2 is methyl or other lower alkyl group.